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CVEN 303 Civil Engineering Measurement
Laboratory Manual
Prepared by Sanjay Tewari & Nasir G. Gharaibeh
Zachry Department of Civil Engineering
Texas A&M University
2013
Lab assignments are subject to change. The instructors will notify the students of any changes.
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LAB#1:SafetyGuidelines,FieldNotesFormat,&SettingupaTotalStationLab Safety Requirements
1) The instructor will explain the safety guidelines for this lab 2) Every student must complete the following required tasks, and sign and return the lab safety
agreement to the TA
Task 1: Review the following Student Safety Guidelines
Safety is a priority at Texas A&M University
These safety guidelines are provided to help prevent accidents. The goals are:
1. To avoid accidents in the lab, and 2. To respond promptly and appropriately should an accident occur.
Safety depends on you!
Students must be careful about their own safety and the safety of others during the lab.
Potential Physical Hazards Include:
Conducting surveys in the open with the potential for sunburn, heat exhaustion, and insect bites, etc.
Setting construction stakes with potential for bruises Working on and near streets with active traffic
Potential Accidents and Responses
Cuts and bruises i. First aid kit will be present in equipment room
ii. Severe injuries require calling 911 Heat exhaustion & sunburns
i. Students will be monitored by GATs ii. First aid kit will be present in equipment room
iii. Severe injuries require calling 911
Task 2: Complete and Sign the Student Safety Contract Agreement (provided on the next page of this handout) and Give it to Your Lab Instructor
Task 3: Sign Lab Safety Agreement (LSA) in Howdy
a. Log into howdy.tamu.edu b. Click on your CVEN 303 c. Click on the link for “LSA” d. Click the checkbox indicating you agree to abide by the LSA
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Student Safety Contract Agreement
Look College of Engineering
Texas A&M University
By signing this form, I verify that I have read, understood, and agreed to follow the safety regulations required for this course as established by the Look College of Engineering and Texas A&M University. I have located all emergency equipment and personal protective equipment, and now know how to use it. While in the laboratory, improper conduct and horseplay of any kind that may endanger others or myself will not be tolerated and appropriate disciplinary action will be taken. I understand that I may be dismissed from this laboratory for failure to comply with the established safety procedures for this laboratory, and with all TAMU & TEES Safety Rules:
Date: ________________
Course: __________________ Section: ______________________
Instructor: ___________________________________________________________________
Student Name (print): __________________________________________________________
Address: __________________________________________ Phone: ____________________
Email: ____________________________________________
Person(s) to be notified in the event of an accident of emergency:
Name (print): ___________________________________ Relationship: __________________
Phone (home): ________________________________ Phone (work): ___________________
(Optional: Any special medical conditions or other comments pertaining to laboratory safety)
Signature: _________________________________________________________
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Field Note Format 1) Follow all 1-34 instructions as shown in the “Field Note Check List” (see Attachment 1). 2) Follow instructions to enter field notes in field books.
Total Station Set-up and Basic Operation Procedure The lab instructor will demonstrate how to set up a Total Station (most commonly used instrument in this course). These instructions can also be found in your textbook (Surveying, 8th Edition, by J. Kavanagh) on pages 133-134. Similar instructions can be found in any other surveying book or online. They are also provided here for your reference (see Attachment 2). After following instructions as shown in Attachment 2, we should have Total Station centered and leveled over a given point.
To turn the Total Station on (after you make sure that is centered and leveled properly), press the right most button on the keypad (on). Once pressed, the LCD screen will show a cross-wires, circle, and electronic bubble. You can see bubble only if instrument is approximately leveled otherwise it will be out of range and you will not see any bubble (you will see only the cross-wires and a circle). Bring the bubble to the center by adjusting the level screws. Double check if the instrument is still on the given station using optical plummet.
1) Now press F1 (CONT) it will take you to “Main Menu”. 2) You need to enter atmospheric data for ppm correction. Press FNC button, it will take
you to “Function selection” screen. Option 1 should be highlighted (black), press enter ( ) and you will see PPM screen. Enter temperature, atmospheric pressure, relative humidity and it will show you ppm total. Now press F1 (CONT). You are back to Main Menu screen.
3) You need to enter basic information for the setup of this instrument, press F5 (SETUP) and it will take you the “Job settings” screen. You need to enter station details so press F1 (STN). It will take you to “Enter Station Data” screen. You need to enter details of the station as per instructions given in lab. This data will be for the instrument station. Once you are done press F1 (CONT).
4) After step 3, you should be on the “Measure & Record” screen. Enter reflector point ID, reflector height information and other information as required. Now you are all set to take readings and the next step depends on the type of survey you plan to do.
5) Pressing F2 (DIST) will let you measure the distance between instrument and reflector you are pointing to. If the screen doesn’t display the data you want to record, press DISP once or twice and it will show you different display settings and you should be able to see the data you want to record.
6) Once you are done taking readings, switch it off and bring back leveling screws to the middle and put the instrument back in its box, as instructed. Never leave instrument box open while working out in the field.
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Attachment#1
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Attachment#2
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LAB#2:TotalStation–HorizontalandZenithAngleMeasurementandCalculationofX,YCoordinatesObjectives
1) To practice setting up a Total Station over a point. 2) To practice measuring horizontal angles to 30” accuracy and measure zenith angles. 3) To record distances of ‘to’ stations from base station. 4) To determine X, Y coordinates of ‘to’ stations knowing coordinates of occupied
station.
Field Procedure 1) Setup Total Station on station assigned to you in the lab (follow the field demonstration).
Follow the instructions given to you in the last lab (see “Basic Operation Procedure of Total Station” section of this handout).
2) Enter atmospheric conditions for ‘ppm’ correction and occupied station information in the Total Station and make it ready for lab experiments.
Steps for Measuring Horizontal Angles
1) Back sight the specified point (Bench Mark GA02) and set Hz angle to zero, as demonstrated by the instructor.
2) Measure and record distance from this point. 3) Measure and record angle right between this BM and foresight point 11 (Direct and
Reversed). Calculate the average angle. Also record distance between base station and point 11.
4) Repeat steps 1-3, except this time you will set Hz angle zero to the last point you shot at and calculate angle. Keep doing this until you are back to first back sight station.
5) Close the Horizon: You and your crew mates will take turns to measure angles as mentioned in step 3. Now compute the horizon closure,
HC = Sum of mean angles - 360° 6) Perform the quality check: HC<Allowable Closure
Where Allowable Closure (AC) = ±30”√n; where n= number of angles Zenith Angles
1) Level the instrument as accurately as possible 2) Point the station you are shooting at and record the Zenith angle in Direct mode (ZD) 3) Put Total station in reverse mode and shoot that point again and record Zenith angle in
Reverse mode (ZR) 4) Verify that ZD + ZR = 360 ± 60”
Basic Operation Procedure of Total Station
1) Press F1 (CONT) to go to “Main Menu.” 2) You need to enter atmospheric data for ppm correction. Press FNC button to go to
“Function selection” screen. Option 1 should be highlighted (black), press enter ( ) and you will see PPM screen. Enter temperature, atmospheric pressure, relative
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humidity and it will show you ppm total. Now press F1 (CONT) to go back to the Main Menu screen.
3) You need to enter basic information for the setup of this instrument, press F5 (SETUP) to go to the “Job settings” screen. Press F1 (STN) to enter station details on the “Enter Station Data” screen. You need to enter details of the station as per instructions given in lab. This data will be for the instrument station. Press F1 (CONT) when you are done
4) After step 3, you should be on the “Measure & Record” screen. Enter reflector point ID, reflector height information, and other information as required. Now you are all set to take readings and next step depend on the type of survey you plan to do.
5) Pressing F2 (DIST) to measure the distance between the instrument and reflector you are pointing to. If you do not see the data you want to record on display, press DISP once or twice and it will show you different display settings and you should be able to see the data you want to record.
6) Once you are done taking readings, switch the Total Station off and bring back the leveling screws to the middle and put the instrument back in its box as instructed. Never leave instrument box open while working out in the field.
The TA will provide values for the following parameters based on weather forecast: Humidity: (e.g., 41%) Pressure: (e.g., 30.02 in.) Temperature: (e.g., 95 F)
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LAB#3:TotalStation–TraverseSides&InteriorAnglesObjectives
1) Tie in all traverse stations: This will be done while you are not involved in taking measurements.
2) Measure traverse interior angle: Each student will measure at least one interior traverse angle. This will be done in “shifts”. The first shift stays in the field to take measurements while other shifts take recovery/ tie-in notes for each station.
3) Write field notes for horizontal angle measurements by repetition: Each student will use tab sheet provided to report: horizontal angle direct 1D, and the 2nd repetition 1D1R value and the average horizontal angle.
4) Compile data for a complete traverse: Upon the completion of the field work, you all will share their measurements with other crews and compile data for a complete traverse. You will have multiple readings for same distance and angles.
Total Station Preparation (see detailed instruction on next page)
1) Setup Total Station on station assigned to you in the lab (vertex in the figure below). Follow field demonstration and instructions provided to you in the previous labs.
2) Enter atmospheric conditions for ‘ppm’ correction and occupied station information in the Total Station, so and make it ready for the lab.
Humidity: ______%; Pressure:______ in.; Temp:______F Horizontal Angles
1) Back sight a given point (B.S. point) and set Hz angle to zero, as shown by the instructor. Measure and record right interior angles. Always take readings in clockwise direction.
2) Measure and record distance between the vertex (Total Station point) and the B.S. point.
3) Measure and record angle right between the B.S. point and foresight (F.S.) point. 4) Obtain direct and reversed angle readings and calculate their mean for each angle. 5) Record distances between base station (vertex) and adjoining traverse stations.
Recovery Notes
1) Write description of each traverse station (what is it, where is it and also provide tie-in notes)
2) Provide at least one direction and one distance info or two distances for the same station from two well known, visible and stable points.
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3) Use one complete spread of your field book. Basic Operation Procedure of Total Station
Once you have centered and leveled Total Station on the base station and you have brought the electronic bubble in the center of the display circle, apply the following steps:
1) Press F1 (CONT) to go to “Main Menu”. 2) Enter atmospheric data for ppm correction: Press FNC button, it will take you to
“Function selection” screen. Option 1 should be highlighted (black), press enter (┘) and you will see PPM screen. Enter temperature, atmospheric pressure, relative humidity and it will show you ppm total. Now press F1 (CONT). You are back to Main Menu screen.
3) Enter basic information for the setup of the instrument: Press F5 (SETUP) and it will take you to the “Job Settings” screen. Press F1 (STN) to enter station details. This will take you to “Enter Station Data” screen. You need to enter the details of the instrument station (this information will be given to you in lab). Press F1 (CONT), when done.
4) After step 3 you should be on “Measure & Record” screen. Enter reflector point ID, reflector height, and other information as required. Now you are all set to take readings and next step depend on the type of survey you plan to do.
5) Pressing F2 (DIST) will let you measure the distance between instrument and reflector you are pointing to. If you do not see information you want to record on display, press DISP once or twice and it will show you different display settings and you should be able to see the data you want to record.
6) Once you are done taking readings, switch the instrument off and bring back leveling screws to the middle and put the instrument back in its box as instructed. Never leave instrument box open while working out in the field.
Note:To hold Total Station for horizontal Angle reading press “SetHz” and then display will give you options, choose “HOLD” and press F5 key. Now put Total Station telescope in reverse mode and bring cross to the station you want to shoot at and press “SET”. This will set last reading you took for horizontal angle to this station and you can take next reading in reverse mode. ----------------------------------------------Cut Here-----------------------------------------------------------
Crew #____________ Name:_________________________________________
Station Occupied:_______________________________________________________________
Backsight Station:__________________ Backsight Distance____________________________
Foresight Station:___________________Foresight Distance_____________________________
Horizontal Angle 1D (Deg. Min. Sec.):______________________________________________
Horizontal Angle 1D1R (Deg. Min. Sec.):____________________________________________
Horizontal Angle Average 1D1R/2 (Deg. Min. Sec.):___________________________________
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LAB#4:ConstructionStakeoutusingTotalStation
Objective
Set building corners with instrument set up on given station and check the accuracy of the building layout. Use 1:5000 for specs.
Office Calculations
Given: A rectangular building is to be staked in the given site. Footing dimensions are as follows
Side a/b b/c c/d d/a
Length, ft 40.00 20.00 40.00 20.00
Side ab is parallel to the line connecting your instrument station and point 12 (baseline) and corner ‘a’ is located at 5 ft (towards point 13) on the perpendicular offset of baseline at point ‘e’ which is at (1/4) of the baseline length from your instrument station.
Calculate: Distances of all four corners of the building from instrument station and their respective angles (in degree min. sec.) with baseline.
Procedure
1) Setup total station on your assigned station.
2) After centering and leveling, enter atmospheric data for ppm correction.
3) Then shoot station 12 find distance and set horizontal angle zero.
4) Now based on your calculations, start locating a, b, c and d corners of the building.
Field Checks
1) Measure sides ab, bc, cd and da.
2) Also, measure both diagonals.
3) Measure angle between ad and ab; cb and cd. They each should be 90°.
The diagonals should, of course, be equal. You can determine what the correct length of each diagonal should be by applying the Pythagorean Theorem. For a large rectangle, checking the accuracy of the stakeout by angular measurement with the Total Station may be more convenient. The corresponding angles at the other three corners should have the same dimensions. If the sizes as actually measured vary at any corner, the stakeout is inaccurate.
Remembering the angles may be necessary to obtain the correct angular precision for the lengths of the lines being checked.
Instruments: Total Station, Pin Flags, Reflector with pole, Tripod, Tape (ft). Data for ppm: Temperature ______F, Humidity ______%, Pressure ________in.
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Wet-weather option:
In case we have rain, we will do this lab in the basement of the Civil Engineering building. Instead of staking out the building mentioned in the handout, we will stake out columns of various dimensions. The Teaching Assistant (TA) will assign base station for each group; you will setup Total Station at your assigned station. Each group will have different station ‘12’ as marked by TA. You will get distance between base station and station ‘12’ and set this direction to ‘zero’ as explained in lab discussion session. Instead of marking point ‘e’ at one fourth distance you will come back 5’ from station ‘12’ towards your base station and you will have offset of 2’. This should give you enough information to calculate distances and corresponding angles for each corner of the column. Conceptually you are doing the same task which you were going to do if it was not raining; but now you are doing this task at a small scale. TA will make sure that you do not get your base station and station ‘12’ in a straight line formed by tiles. Also do not use tape for ‘distance hunting’ (this will defeat the purpose of using Total Station.) Field Checks
1) Measure sides ab, bc, cd and da using tape.
2) Also, measure both diagonals using tape
It is not possible to use Total Station for angle measurement. But if the sides are as long as the given dimensions and both diagonals are equal, it should be a good check.
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LAB#5:TraverseandAutoCADObjectives
1) Use ACAD to plot closed traverse and solve it. 2) Use spreadsheet to calculate, departure, latitude, bearing and azimuth for each side of
traverse.
Problem # 1 A consulting firm has a client that owns hundreds of acres used primarily to raise trees for timber. The firm selects a small parcel of this land by drawing lines and assigning coordinates on a map of the property. They went into the field and drove steel rods in the ground at two of the corners of the proposed properties. The coordinates that they found by scaling of a map are as follows:
(5,000, 3,000) There is an existing steel rod at this location. (4,800, 3,400) There is an existing steel rod at this location. (5,400, 3,300) (5,300, 2,900) (5,200, 3,100) All coordinates are in feet and the coordinates proceed clockwise. Required:
1) Set up an ACAD drawing with the following UNITS:
Length Angle Type Type Decimal Surveyors Units Precision Precision 2 places to 0d00’00” rt of decimal Feet Use default for Direction The units are set up so that directions of lines are expressed as azimuths.
2) Draw the traverse and list each line of the traverse; cut and paste the information for each line provided by the LIST command.
3) Determine the area and the perimeter of the property. Cut and paste this information within the perimeter of the sketch.
4) DIMENSION the interior angles at each corner.
5) Draw a North Arrow and a Scale on the drawing.
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Problem # 2
The information from Problem # 1 is given to a surveying crew so that they actually make measurements in the field and stake out the corners of the proposed property.
1) Their field notes include the following:
Beginning at a point marked with a #6 Bar with assumed coordinates of 5,000.00 ft, 3,000.00 ft, thence a distance of 439.30 ft at a Bearing of N26d33’54”W, more or less, to a #6 Bar with called (assumed) coordinates of 4,800.00 ft, 3,400.00 ft based on a scale drawing; thence a distance of 608.28 ft at a bearing of S80d32’16”E and set #6 Bar; thence a distance of 412.31 ft at a bearing of S14d02’10”W and set #6 Bar; thence a distance of 223.61 ft at a bearing of N26d33’54”W and set #6 Bar; thence to the point of beginning a distance of 232.55 ft at a bearing of S63d26’06”W.
Plot this traverse and determine the error of closure and the precision graphically.
2) If the precision is at or better than 1/10,000 force the correction in the last line by making the final coordinates equal to 5,000.00 ft, 3,000.00 ft and calculate the distance and direction and verify that the traverse closes.
3) Draw the final traverse and dimension the interior angles, determine the area, and list the line (cut and paste).
Problem # 3 Using final and corrected coordinates from above traverse, which are provided below, calculate departure, latitude, bearing and azimuth of each side of the traverse using spreadsheet.
X coor.
Y coor.
A 5000 3000 B 4800 3400 C 5400 3300 D 5300 2900 E 5200 3100 A 5000 3000
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LAB #6: Benchmark Leveling
Objectives 1) Learn basic benchmark leveling techniques using modified 3rd order specifications
(described below). 2) Establish the elevation of BM 12 and BM LQ13 to a precision of ±0.01 ft.
Procedure
1) Practice leveling procedure using automatic level instrument: instrument set up, aiming, focusing and reading the rod.
2) Begin Leg # 1 of the level loop survey at BM GA02. Elevation of BM GA02 is 241.028ft. One student will be the instrument person, one will be the rod person, and the rest will be note keepers. You need to change your roles after each leveling leg so that each student will get to be the instrument person at least once.
3) Run Leg 1. Run levels across Bizzell St. to BM 12, change jobs. 4) Run Leg 2. Run levels from BM 12 to BM LQ13, change jobs. 5) Run Leg 3. Run levels from BM LQ13 to BM GA02.
Specifications
1) Keep sight distances short (less than 200 ft or 70 paces). 2) Keep line of sight 1.0 ft above/away from “heat sources” like ground, cars, bushes etc. 3) Perform calculations (height of the instrument (HI) and elevation), as measurements are taken. 4) Use stakes or selected exact and stable objects for Turning Points (TPs). 5) Balance sight distances at each setup: difference should be ≤ 10 m or 10 paces. 6) Balance total backsight (BS) and foresight (FS) distances at benchmarks: difference
should be ≤ 10 m (or 10 paces). 7) Be prepared for spot field book checks – copies ARE NOT field notes. 8) Field books should be ready to be turned in before leaving the field.
Field Notes
1) BM description/references
2) Math check: End elev. = Start elev. + ΣBS – ΣFS 3) Quality check: EOC (error of closure) < AC (allowable closure) or
calculated elev. – given elev. < ± 0.02√(no. of HIs) ft. Office Problem Adjust the elevations of BM---- and BM----- (valid only if survey meets specs). If the survey does not meet specifications, ideally you should redo it. However, in this lab we will accept the survey so that you can practice with adjustment methods.
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LAB#7:InstrumentCheckusingThreeWireDifferentialLevels&ReciprocalLevelingObjectives
1) To become familiar with 3 wire differential leveling procedures, note form, and data reduction.
2) To perform an instrument check by determining the adjustment of your level line of sight, the angle from horizontal, α.
3) To become familiar with reciprocal leveling concept. Procedure Part A: Instrument Check using Three Wire Differential Levels
Check the adjustment of your level by determining the vertical angle for your level’s line of sight using the Modified Kukkamaki’s Method described as follows:
1) Set 2 stakes (+) for rod positions 20.0 m apart, then set a pin flag (I), halfway between the stakes (10.0 m), as shown in the diagram below. Now extend the line 20.0 m and set a second pin flag (I). All four points should be in a straight line. The pin flags are instrument positions. ENSURE that the site is all shade or all sun. Ensure that the rod can be read WITHOUT extending it!
Inst2 FS Inst1 BS
I------------------------------+----------------I---------------+
< --------20.0 m----------- >< - 10.0 m - >< -10.0 m-- >
1) Set up the Level at instrument position 1 (Inst1), halfway between stakes. Take 3 Wire backsight and foresight readings to 0.001m. Compute the near correct delta elevation (Δ elev1) for the near balanced sight distances, BS ave. – FS ave. Now, compute the minor imbalance in sight dist, Δ dist1 = BS dist1 – FS dist1. This should be about 0.0 m.
2) Set up the instrument on position 2 (Inst2), and take 3 Wire backsight and foresight readings on the same points for backsights and foresights. Compute the delta elevation with imbalanced sight distances, Δelev2 (Δelev1 and Δelev2 should be equal within ±0.002 m to be within specs). Compute the imbalance in sight dist (Δ dist2 = BS dist2 – FS dist2). This should be about +20.0 m.
3) Compute the vertical angle of the line of sight of the instrument, (α), in seconds using:
1 ( 2 1)
( 2 1)
Elev ElevTan
dist dist
check: α ≤ 20” for 3rd Order
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Note: The sign of α is very important as you have the magnitude and the sign of this systematic error. Part B: Reciprocal Leveling Procedure
1) Setup level and take BS reading on a near point (call it ‘A’) and FS reading on a far point (call it ‘B’). In this case the readings are not balanced.
2) Now go to a far point (say a cross a river or a valley) and set up the instrument there. Take BS reading again on ‘A’ and FS reading on ‘B’. This time BS is long and FS is short, which is opposite of first setup situation.
3) Average the elevations of point ‘B’ 4) Point ‘A’ will be BM LQ09 (elevation 234.364ft.) and point ‘B will be BMLQ13.
Equipment Parts A and B 1 Auto Level 1 Tripod 1 Level Rod (Ft)
I Level Rod (meter) 2 Hubs 2 Pin Flags 2 Nails 1 Tape (30 Meter) 1 Hand Axe Note: In reciprocal leveling averaging process eliminates instrumental errors and natural errors, such as curvature. Error due to refraction can be minimized by ensuring that the elapsed time for the process is kept to a minimum.
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LAB#8:ProfileandCrossSectionLevelingObjectives
1) Practice basic profile and cross section leveling techniques. 2) Establish horizontal control along a proposed center line: full stations (100 ft.), half
stations (50ft.) points and grade breaks. 3) Set horizontal control points along right of way (ROW) lines. ROW lines are
boundary lines located at 50 ft to the right and left of the centerline. 4) Determine elevation for profile and cross sections to ±0.1 ft for “ground” shots.
Procedure
1) Set the horizontal control (the lab instructor will assist in this task). 2) Crew #1 will set the profile center line to include full stations and half stations.
(Mark the points with taping pins using one color of flagging for all stations and half stations.)
3) Crew #2 will set the left ROW line. (Mark grade change points along left ROW with different color flags.)
4) Crew #3 will set the right ROW line. (Mark grade change points along right ROW with different color flags).
5) Crew #4 will mark the grade change points along cross sections at every station and half stations using different flags/taping pins.
Notes:
1) Record centerline data along center line (I) and offset data as intermediate shots (IS) Left IS IS I IS IS Right 50 o/s o/s 50 Where o/s stands for offset from centerline
2) When recording your data, skip two lines between station/substation entries so that the “Calculated Elevation” can be recorded above IS at o/s.
3) Grade change points and offset, o/s, data must be taped and recorded by each crew. 4) Record profile and cross section leveling data to obtain elevations at all marked stations,
grade change points, and offsets. Begin survey at BM LQ 9 (Station 1) 5) Perform the field checks: math and quality control (QC) checks before leaving the site.
QC: Error of Closure<Allowable Closure (AC) AC = ± 0.02(n)0.5
ft. where n = number of HIs (or instrument positions)
Math check: End elev. = Start elev. + ΣBS – ΣFS 6) Compute elevations at all points observed to proper precision: Rod readings for BMs, TPs, and exact stable profile cross section points are to ±0.01 ft; “ground shots” at profile and cross sections to ±0.1 ft.
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Office Problem: Plot center line profile. Scale: 1 in. = 50 ft horizontal, 1 in = 5 ft vertical Note: Record centerline profile data (station and elevation) as follows, for lab homework exercise. Station __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ __ Elevation
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LAB#9:LeicaGPS900BasicSetupandRecordingofPointCoordinatesObjectives
1) To learn how to setup a GPS unit (we will use the Leica GPS 900 unit). 2) To learn how to set up a reference a point (base station), perform localization, and
record coordinates of points (northing, easting, and elevation).
Procedure
1) The Instructor will demonstrate how to setup the GPS unit and its basic operation for collecting coordinates of points. A GPS manual is provided in Appendix A to help you learn the process.
2) The class will be divided into crews. Each crew will set the GPS base unit up over point LQ13 (reference point) and collect the coordinates of points LQ09, 11, 12 and 13.
3) While one crew is setting up the unit and collecting coordinates, the other crews will observe.
4) When you finish taking GPS readings, shut down the GPS unit and place it back in the instrument case.
5) The next crew will take over and repeat the above steps.
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LAB#10:GPSApplicationinControlSurvey
This is an indoor lab that involves performing various computations for determining grid distance and distance at sea level using surface distance; and vice versa.
Specific problems will be provided and discussed during this lab.
LAB#11:RepeatofLab9(SetupandOperationofGPSunits)&LabQuiz
Practice with Leica GPS 900 unit. Lab Quiz.
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LAB12:SettingoutHorizontalCurveUsingDeflectionAnglesObjectives
1) Learn to use total station for setting out horizontal curve. 2) Establish point of intersection (PI) and end of curve (EC) given point of start of
beginning of curve (BC). 3) Establish intermediate points for the curve using deflection angles method.
Procedure
1) Set the point BC as instructed by the lab instructor: 2) Setup Total Station over point BC and find PI in the suggested direction by measuring
distance with the help of reflector mounted on top of pole, do not forget to enter ppm data in Total Station and basic information of instrument height and height of reflector.
3) Now establish point EC by setting up Total Station at point PI and deflection angle and subtangent (T) distance. Make sure you enter new height of instrument in the Total Station for new setup.
4) Now go back to point BC set your Total Station on BC and enter new height of instrument again and start shooting for intermediate points by measuring distances and deflection angles. Make sure you setup Horizontal angle to zero along line BC-PI before you start shooting points. Mark every point with colored flags.
5) Once you locate EC again based on calculations below and deflection angle/chord distance method, measure the distance between the two EC points. This will be error and this might be because of rounding off error and/or manual and systematic error during measurements.
Given:
Use Deflection Angle = (arc/L)*(Δ/2) and Chord = 2R*Sin(deflection Angle) to calculate deflection angles and chord distances as instructed in the class by the faculty.
Sta BC 1+55 155.03Sta PI 3+00 300Sta EC 4+30 429.92T = 144.97L = 274.89Δ = 45°Radius 350
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Calculations:
Sta. Curve length segment Deflection
angle
Cumulative deflection angle in
Degrees Chord
Distance Cumulative deflection
angle DDMMSS
1+55 0.00 0 0 0.00 0d0'0"
2+00 44.97 3.680836 3.680836 44.94 3d40'51'
2+50 50.00 4.092546 7.773382 94.68 7d46'24"
3+00 50.00 4.092546 11.86593 143.94 11d51'57"
3+50 50.00 4.092546 15.95847 192.46 15d57'30"
4+00 50.00 4.092546 20.05102 240.00 20d03'04"
4+30 29.92 2.44898 22.5 267.88 22d30'00"
Data for ppm correction in Total Station: (The TA will provide values for the following parameters based on weather forecast) Humidity: (e.g., 41%) Pressure: (e.g., 30.02 in.) Temperature: (e.g., 95 F)
FIGURE 1. Circular curve terminology
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LAB#13:BuildingStakeoutusingLeicaGPS900(Optional,TimePermits)Objectives
1) To learn how to setup a GPS rover and base station (repeat Lab # 9). 2) To learn how to stakeout a building using GPS unit.
Procedure
1) You will be divided in crews and each crew will setup GPS unit. After basic unit setup, which you have learned in your last lab, instructor will show you how to use stakeout mode for this lab.
2) We will give local coordinate of (0, 0) to our base station and based on dimensions of the building (20ft x 40ft), we will enter coordinates of remaining three corners assuming that (0, 0) is one of the corner of the building.
3) Once in stakeout mode, GPS unit will guide you towards remaining corners, with arrow for direction and distance you need to travel in that direction.
4) One thing you should keep in mind that GPS works better if you constantly move. If stay still and do not move, GPS unit will not be able to guide you accurately. So it’s a good idea to move slowly and continuously.
5) When you will approach near the target point. Pay attention to beeping sound. This sound will become increasingly fast as you go closer to the point.
6) While one crew is setting up the unit and collecting coordinates, the other crews will observe.
7) When you finish taking GPS readings, shut down the GPS unit and place it back in the instrument case.
8) The next crew will take over and repeat the above steps.
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LAB#14:SlopeStakeUsingAutomaticLevel(Optional,TimePermits)Objective
To learn how to use an engineering level in a reconstruction project in which a sidewalk will be constructed adjacent to the Civil Engineering Building. Prior to construction the existing sidewalk will be removed and the construction area will be cleared and grubbed.
Assignment
Each student will set out one slope stake. The first assigned side slope will be 1V to 1H. The second and third side slope is 1V to 1.5H and 1V to 2H. Figures are attached.
Procedure
1. Using a cloth tape set a hub stake (call it point A) 12 ft perpendicular distance from the wall of the Civil Engineering Building (See Figure 1).
2. Using the engineering level (set up so that BS distance and FS distance are the same) and bench mark determine the elevation of the existing sidewalk at your assigned location. Use this point as a local bench mark (No Figure).
3. Set up the engineering level about 20 ft to 30 ft from the Civil Engineering Building. Use a hand level to ascertain that the HI will be at least a foot higher than the sidewalk (local bench mark) (See Figure 2).
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4. Determine the elevation of the top of the hub (point A’ by taking a BS on the local bench mark and a FS on the top of the hub. Determine the vertical distance from the elevation of the local bench mark (also the elevation of the existing sidewalk, to the top of the hub. The hub is probably lower than the bench mark; if it is the difference is fill. Determine the amount of fill (or cut) and write it on a guard stake (lath) (See Figure 2).
5. Determine the location of the Slope Stake (Point B) in Figure 3 by trial and error. The first trial is called B’1 and it is 10 ft horizontally from Hub A. The elevation of B’1 is determined by two methods:
First Trial (Point B’1) See Figure 3. 1st by use of the engineering level:
Station BS HI FS Elevation Local BM 1.64’ 102.20’ 100.56’ B’1 5.98’ 96.22’
First Trial Continued 2nd by use of geometry of the cross section.
Elevation of A is known to be the same as the elevation of the Local Bench Mark = 100.56 ft. Side-Slope of Fill is 2H to 1V. H-Distance = 10 ft, therefore V-Distance is 5.00 ft. Elevation of B’1 is 100.56’ – 5.00’ = 95.56’ 95.56’ < 96.22’, therefore 10’ H-Distance is too large.
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Second Trial (Point B’2) See Figure 4 1st Engineering Level Data Station BS HI FS Elevation Local BM 1.64’ 102.20’ 100.56’ B’2 5.08’ 97.12’ 2nd by use of geometry of the cross section. H-Distance is 4.95’, therefore V-Distance is 2.47’ El. B’2 is 100.56’ – 2.47’ = 98.09’ 98.09’ > 97.12’ therefore H-Distance is too small.
Third Trial (Point B) This trial is also shown on Figure 4. It works out!
The elevations are the same by both methods. In the field they should agree to the nearest 0.1 ft or less. The Slope Stake B is located 8.05’ from Hub A. A stake is driven and marked with the following value for fill. El. B = 96.54’ El. Hub A = 100.56’ The fill at B is 4.02’. Round to nearest 0.1’ which is Fill=4.0’
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Appendix A: GPS Setup Manual (Leica GPS 900)
SETUP OF BASE STATION
1. Place tripod over point of known or assumed coordinates. (i.e. Benchmark, Iron Rod, PK nail).
This is your base station or reference point.
2. Take the BASE ARM and TRIBROCK from instrument case and place the Base arm into the
TRIBROCK and lock it into place with the arrow marked lever. When the arm is locked in, the
arrow will be pointing to the bottom of the TRIBROCK.
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3. Place the TRIBROCK/BASE ARM assembly onto the tripod and tighten the screw to where the
assembly is centered on the top of the tripod.
4. Remove GPS receiver labeled BASE RECIEVER from the instrument case and snuggly screw it
down onto the top of the TRIBROCK/BASE ARM assembly.
5. Level and center the tripod over the point of interest.
i.) Sight through the optical plummet to place the BASE RECIEVER over the point by
using the leveling screws on the TRIBROCK.
ii.) Use the screws on the tripod legs to center the bubble on the TRIBROCK and
therefore center the tripod setup.
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iii.) Use the leveling screws on the TRIBROCK to finely adjust the level bubble.
6. Remove METAL BRACKET and radio labeled BASE RADIO from the instrument case and slide the
BASE RADIO onto the METAL BRACKET using the metal guide.
7. Place one of the two BLACK ATTENAS onto the BASE RADIO and attack the METAL
BRACKET/BASE RADIO assembly onto the tripod.
8. Take the Y‐CABLE from the instrument case and find the split end of the cable.
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9. Take the female end of the split and connect it to the BASE RECIEVER by lining up the red marks
and gently pushing the cable in.
10. Take the male end of the split and connect it to the BASE RADIO by lining up the red marks and
gently pushing the cable in.
11. Position the GEL CELL BATTERY under the tripod, but not over your point, and insert the single
end of the Y‐CABLE by lining up the red marks and gently pushing the cable in.
WANRING: Do not force the cables in. they will go in easily if the marks are properly aligned.
12. Power on the BASE RECIEVER by pressing and holding the on/off button on the BASE RECIEVER
until the unit lights up and a yellow and green are shining in two of the three slots.
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SETUP OF THE ROVER
1. Remove the ROVER BRACKET and ROVER RADIO from the instrument case and slide them
together using the ROVER RADIO connection as a guide.
2. Take one of the four batteries from the case and place it onto the back of the ROVER BRACKET.
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3. Take the ROD CLIP AND SCREW from the case and loosely attach it to the ROVER BRACKET.
Loosely means clip should be able to rotate freely.
4. Take DATA COLLECTOR from the case and place one of the four batteries into the back of the
DATA COLLECTOR by unlocking the back panel.
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5. Place DATA COLLECTOR onto the ROVER BRACKET by lining up the metal clip on the bottom of
the DATA COLLECTOR with the ROVER BRACKET hook. Use the palm and fingers to press the
DATA COLLECTOR down and attach it to the ROVER BRACKET.
6. Take the second BLACK ATTENA and attach it on the ROVER RADIO.
7. Take prism rod of which you plan to use for you survey and slide the rod through the ROD CLIP
AND SCREW (the bottom of the rod goes through first).
8. Position the ROVER BRACKET assembly to where the level bubble can be seen easily while
looking at the DATA COLLECTOR.
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9. Take ROVER RECIEVER from the case and place a battery into the bottom of the receiver.
10. Screw the BASE RECIEVER onto the prim rod.
11. Power on the ROVER RECIEVER by pressing and holding the on/off button on the ROVER
RECIEVER until the unit lights up and a yellow and green are shining in two of the three slots.
12. Power up the DATA COLLECTOR by pressing and holding the PROG button until the Leica logo
flashes up on the screen.
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REFERENCE POINT SETUP
To set up your reference point of the GPS Base Station you will need to follow the instructions given in
the Instrument Assembly portion of the GPS manual. Then continue on with the following instructions.
1. Once you are looking at the main menu of the DATA COLLECTOR choose the Programs folder of
the menu and then choose the Setup Reference on the task menu under Programs (it will be the
first on the task list).
2. Now, continue to name the job and set your Coordinate System to be WGS 1984 and set the
code list to none.
3. The next two screens will be default in the unit, so continue onto the next screen.
4. Now you need to set the base point for your base station. Name the point and measure the
antenna height using the measure rod in the instrument case.
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5. Once you have entered in that information you now have two options: 1) you can input the
known coordinates of a point that you are occupying if you know the coordinates of that point,
or 2) you can use a here position which will set the location that you occupying to Texas State
Plane coordinates. Store this point and ESC back to the main menu.
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One Step Localization
This is a step by step process of the One‐step Localization of the Leica GPS900 Survey Unit. This process
follows that of the initial setup of the unit as well as powering the unit on as described in the Instrument
Assembly part. Your Reference Setup will be a Here position located centrally in your survey field.
1. Once you are looking at the main menu of the DATA COLLECTOR you will setup a job which
will be you Local desired coordinates called: LOCAL and a GPS coordinate job called
GPS(these names are arbitrary and you may name them whatever you desire).
First open the Manage Jobs Folder
Then choose Jobs
Then choose New(F2), name the job Grid Job and give the job creator’s name
Then page over to Coordinate System and set it to WGS1984
Once you have named the job choose Store and it will bring you back to the jobs folder
Once in the jobs folder make sure Grid Job is highlighted and choose Data
Once in Data choose New(F2), name the point Base and set the X coordinate to 0 and
the Y coordinate to 0 and the Z coordinate to 0, this will set up our origin, then store the
point
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Now use the ESC button to get back to the Manage Jobs Folder
Choose Jobs and then choose New(F2), name the job WGS84 Job and give the creators
name and once again make sure the coordinate system is WGS1984
No Data points will be stored in this job at this moment
Now ESC out to the main menu
2. Now that our jobs are set up we will now begin to survey a point in order to place our
created coordinate system and place it onto the local site we will be surveying.
Choose the Programs folder on the from the main menu and then choose the survey
task on the list of commands
Make you store the point we are going to survey is under the Job of the WGS84 Job
Once you have the correct job you will continue on to the occupy screen
Name the point GPSBase and hold the Rover leveled over the point of which you wish to
set your Origin of the system
Occupy the point by pressing F12
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Now you are ready to setup the coordinate system so ESC out to the Programs task page
3. Now that you have all the points you need to create a coordinate system you can now setup
your survey.
Choose the Programs Folder from the main menu and then Choose the Determine
Coordinate System from the Task menu
Now name the coordinate system set up the WGS84 points job the Job of which you
took the GPS point and set the Local points job to the job of which you stored in the
base point
Then choose the method of the system to be One Pt Localization then press F1 to
continue
Once on the next screen, choose the height mode to be Orthometric and press F1 to
continue
The Geoid Model will set to known and you continue to the next screen
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Now you will be on the screen where you set the point you entered and the point that
you surveyed to laid on top of each other
Continue through the rest of the default screen and finally store the coordinate system
into the collector
Now you can use your new coordinate system with any survey that you do.
